Bitter orange, hardy orange, trifoliate orange, Japanese hardy-orange The dwarf form with curved spines is called "Flying Dragon" and has sometimes been given the common name "pain and terror" See: http://articles.orlandosentinel.com/1988-09-06/news/0060420012_1_shivers-trifoliate-orange-pain-and-terror = Citrus trifoliata Rutaceae > The rue family.